Topics include: Maureen Dowd of course, the Church of the Savvy, One year of Twitter for Jay. Why is user interface so damned hard? 10 years since Edit This Page. And an inspired choice for Inspiration of the week, Elvis Costello's recording of Nick Lowe's classic What's So Funny 'Bout Peace Love and Understanding.

First an update on today's earlier blog post. Apparently Google Reader does not support reading lists. I think when I asked the question, the 140-character limit on Twitter made it impossible for an accurate answer.

No matter what, maybe it would be a good idea now to try to give a complete technical explanation of what a reading list is.

1. There are many kinds of "feed consumer" apps, all of them are capable of supporting reading lists, not just feed readers or aggregators. In the rest of this piece I'll use the shorthand "FC" to refer to a feed consumer app.

2. When you subscribe to a feed you're telling the FC that you want it to periodically read the contents of that feed and somehow act on the new items in the feed.

3. A reading list contains a set of feeds. The format of a reading list is exactly the same as the OPML-based subscription list format that's supported by many FCs.

4. When a FC subscribes to a readling list it does not import the feeds.

5. When the FC checks for updates, it checks for new items in the feeds in the reading list. Therefore it must keep a record of the feeds in the reading lists it is subscribed to.

6. If a new feed appears in the reading list, it does whatever it does for a new feed. Many FCs will consider all the items in the feed as "old" the first time the feed is read, esp if it's a podcatcher.

7. If a feed that was in the reading list has been removed, then the feed is not read and all record of the feed is erased from FC database, with the following exception. If a feed appears in two or more reading lists, a reference count must be maintained, and the feed is erased only when the reference count goes to zero.

8. Obviously the user can subscribe to as many reading lists as he or she likes.

9. The behavior I've described is how the NewsRiver aggregator that runs in the OPML Editor works. I suppose it's possible that other FCs work differently. If so, it would be great to hear about them.

I think that pretty much covers it.

Google's incomplete support of reading lists

Kevin Marks, who works at Google, tells anyone who will listen that Google Reader has a new feature that's exactly like reading lists, and that's a good thing -- because they are powerful and useful, and likely a key to making news reading work for more people.

Reading lists allow you to delegate subscription to feeds to experts. So for example, I could let Lance Knobel, an economist who I trust, choose the feeds I follow in his area of expertise. That way, when a new feed comes along, instead of sending me an email saying "Hey Dave you might want to subscribe to this feed" he can do it for me simply by adding it to his reading list.

Similarly, if a feed is no longer being updated, when Lance unsubs from it, so will I, automatically.

You can think of reading lists as a mutual fund of feeds. Busy people don't have time to research which feeds to follow and unfollow, so they delegate that to experts.

Another application -- the BBC has a large number of feeds, some for special events like the Olympics or elections. They could have a reading list for all their feeds, and when one falls off, they'd remove it, and when a new one comes on, they could add it.

It's an obvious extension to RSS, and to the ability to import and export OPML subscription lists. You can subscribe to a list of feeds in addition to individual feeds.

Now I'd love to provide reading lists for users of Google Reader, but I can't because they're using an incompatible format. This is absolutely the wrong thing to do. When asked to explain why, Marks gives a nonsense answer about the OPML Editor, which this has nothing to do with. It's always a shame when technologists, who have to answer precisely to the computer, use political spin when talking to users.

Further, if Google plans to challenge Twitter, as I've said I hope they do -- they will not get my support if they respond to Twitter's locked trunk with their own locked trunk. They must use RSS, OPML, Atom, everything they can find that there is even a bit of consensus for, including Twitter's API. They must achieve a remarkable level of compatibility to make the barrier to entry as low as it possibly can be and to send a signal that they just want to be a player in the market, not the dominator of the market.

Google's attitude in this area has been very unfortunate -- they've tended to be incompatible with existing formats whenever they can get away with it.

If Google had not invented a new format for reading lists, this would be a very different post. I'd be offering some reading lists of my own for their users to subscribe to, and encouraging my colleagues to do the same. I'd have written a howto that shows people what they need to do to create a reading list for Google Reader if they don't use Google Reader.

It's bad strategy to be gratuitously incompatible. It's also bad manners. Google was given a market for their reader built on open formats. They ought not consume that open-ness, they ought to at least preserve it, if not enhance it.

However, I will sing their praises if they fix their implementation to use the same format we use for their implementation of reading lists. If not, we'll wait to see what their efforts to compete with Twitter look like.

Last update: Sunday, May 24, 2009 at 9:39 PM Pacific.

Dave Winer, 54, pioneered the development of weblogs, syndication (RSS), podcasting, outlining, and web content management software; former contributing editor at Wired Magazine, research fellow at Harvard Law School, entrepreneur, and investor in web media companies. A native New Yorker, he received a Master's in Computer Science from the University of Wisconsin, a Bachelor's in Mathematics from Tulane University and currently lives in Berkeley, California.

"RSS was born in 1997 out of the confluence of Dave Winer's 'Really Simple Syndication' technology, used to push out blog updates, and Netscape's 'Rich Site Summary', which allowed users to create custom Netscape home pages with regularly updated data flows." - Tim O'Reilly.